refactor: Bundle GPU context into GpuContext struct

- Created GpuContext struct {device, queue, format}
- Updated Effect/PostProcessEffect to take const GpuContext&
- Updated all 19 effect implementations
- Updated MainSequence.init() and LoadTimeline() signatures
- Updated generated timeline files
- Updated all test files
- Added gpu_get_context() accessor and fixture.ctx() helper

Fixes test_mesh.cc compilation error from g_device/g_queue/g_format conflicts.
All targets build successfully.

1 files changed, 3 insertions, 5 deletions

diff --git a/src/gpu/effects/chroma_aberration_effect.cc b/src/gpu/effects/chroma_aberration_effect.cc
index 6e64988..83c5f2a 100644
--- a/src/gpu/effects/chroma_aberration_effect.cc
+++ b/src/gpu/effects/chroma_aberration_effect.cc
@@ -5,14 +5,12 @@
 #include "gpu/gpu.h"
 
 // --- ChromaAberrationEffect ---
-ChromaAberrationEffect::ChromaAberrationEffect(WGPUDevice device,
-                                               WGPUQueue queue,
-                                               WGPUTextureFormat format)
-    : PostProcessEffect(device, queue) {
+ChromaAberrationEffect::ChromaAberrationEffect(const GpuContext& ctx)
+    : PostProcessEffect(ctx) {
   uniforms_ =
       gpu_create_buffer(device_, sizeof(float) * 6,
                         WGPUBufferUsage_Uniform | WGPUBufferUsage_CopyDst);
-  pipeline_ = create_post_process_pipeline(device_, format,
+  pipeline_ = create_post_process_pipeline(device_, format_,
                                            chroma_aberration_shader_wgsl);
 }
 void ChromaAberrationEffect::render(WGPURenderPassEncoder pass, float t,